排序方式: 共有13条查询结果,搜索用时 15 毫秒
1.
2.
The ecological effects of planting exotic Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] in Central Europe are still poorly understood. The aim of this study was to answer the question of whether Douglas-fir affects tree specific arthropod communities in different mature forest types (Douglas-fir, spruce and beech dominated) in Southern Germany. Therefore, arthropod communities of stem and tree crown strata of Douglas-fir and spruce (Picea abies L.) were sampled in the years 1999–2001 using arboreal photo-eclectors and flight interception traps. Statistical analysis was conducted for all species and focused on conifer specialists at three levels: (1) species diversity, (2) guild structure and (3) community structure. Within the stem stratum, species diversity was significantly higher on spruce than on Douglas-fir independent of year and stand composition. This could not be explained by a single feeding guild, rather by species changing strata during the vegetation period. In contrast, species diversity in tree crowns was approximately the same for both conifer species. However, communities in Douglas-fir crowns were conspicuously different from those in spruce crowns, especially in the Douglas-fir dominated stand type. While zoophagous insects exhibited higher activity on Douglas-fir in 2000, xylophagous beetles were more abundant on spruce in 2001. In European beech stands with widely spaced Douglas-fir trees, the site specific and broad-leaved tree related fauna might be maintained. In addition, Douglas-fir with its resource of Adelges cooleyi and crowns that overtop the broad-leaved tree canopy, offer additional resources for several aphidophagous and thermophile species. 相似文献
3.
The effects of pesticides on beneficial predatory arthropods have been widely studied; this paper however deals with their effects on Heteroptera, an important beneficial insect group and food source for farmland birds. Field trials were used to evaluate pesticide effects under realistic conditions of application on a commercial arable farm and compared with previously published laboratory findings. Fungicides were found to produce very low levels of mortality, not significantly different from control treatments. Aphicides varied in their impact, producing non-significant to highly significant mortality levels. The likely ecological impact of pesticides on various heteropteran groups found within the field and field boundary is discussed. © 1997 SCI. 相似文献
4.
记述采于我国南方地区猎蝽两种新种:王氏长头猎蝽,新种Henricohahnia wangi Ren,sp.nov.及广西刺猎蝽,新种Sclomina guangxiensis Ren,sp.nov。文中附特征图(图1-图13)。模式标本存放在南开大学生物昆虫标本室,天津。量度单位:mm。 相似文献
5.
本文从半翅目昆虫的禾本科寄主、取食各类禾本科植物的半翅目昆虫、半翅目昆虫对禾本科植物的取食情况等相互关系作了论述和分析。 相似文献
6.
分析比较了河南半翅目蝽科昆虫的世界动物区系和我国动物区在属级阶元的构成,发现河南蝽科昆虫具有显著的东洋区系性质,在我国动物区系亚区水平上以华中区系和西南区系成分为主。 相似文献
7.
河南省半翅目昆虫区系潜在物种数量分析 总被引:3,自引:1,他引:3
对河南半翅目昆虫的资源进行调查,结果表明,已知的29科222属376种在分类结构上有明显的失衡现象,研究深入的蝽科类群占半翅目比例高达22%,而研究薄弱的盲蝽亚科、网蝽科、及水生半翅目类群相对比例明显偏低分别占6.4%、1.9%、3.7%。保守估计,河南省的半翅目昆虫应该有接近700种规模。 相似文献
8.
Tohidi-Esfahani D Lawrence MC Graham LD Hannan GN Simpson AM Hill RJ 《Pest management science》2011,67(11):1457-1467
BACKGROUND: Certain bisacylhydrazine compounds such as tebufenozide (RH5992) have been shown to act as order‐specific insecticides. Their compatibility with predatory Heteroptera, which are used as biological control agents, has also been demonstrated. However, the molecular mode of action of these ecdysone agonists has not been explored in a heteropteran, much less one that is a significant agricultural pest, such as Nezara viridula. RESULTS: Alternatively spliced ligand‐binding regions of the N. viridula ecdysone receptor were expressed, purified and characterised by 2D gel analysis, mass spectrometry, homology modelling and competitive binding of a bisacylhydrazine insecticidal compound (RH5992) and various ecdysteroids. Ligand binding by the two splice isoforms was indistinguishable, and relative affinities were found to occur in the order muristerone A > ponasterone A > 20‐hydroxyecdysone > inokosterone > RH5992 > α‐ecdysone. CONCLUSION: The predicted difference in amino acid sequence between the ligand‐binding domains of the N. viridula ecdysone receptor splice variants was verified by mass spectrometry. Both splice variant isoforms exhibit a greater affinity for the bisacylhydrazine insecticide RH5992 than do the other hemipteran ecdysone receptors characterised to date. Their affinities for a range of ecdysteroids also distinguish them from the ecdysone receptors of other Hemiptera characterised thus far. Homology models of both N. viridula receptor isoforms provide further insight into the bisacylhydrazine‐ and ecdysteroid‐binding properties of these receptors, including their similar affinity for 20‐hydroxyecdysone and the postulated pentatomomorphan moulting hormone makisterone A. Copyright © 2011 Society of Chemical Industry 相似文献
9.
Luis Lenin Vicente Pereira Kaio Cesar Chaboli Alevi Márcia Maria Urbanin Castanhole Felipe Ferraz Figueiredo Moreira Julianna Freires Barbosa Mary Massumi Itoyama 《Journal of insect science (Online)》2015,15(1)
The Heteroptera have holocentric chromosomes with kinetic activity restricted to the end of chromosomes. The first meiotic division is reductional for the autosomes and equational for the sexual. Only a few species of this suborder have been analyzed. In this study, we observed the morphologies of the testes of the Heteroptera species Belostoma anurum (Herrich-Schäffer, 1948), Belostoma micantulum (Stal, 1858), Gelastocoris angulatus (Melin, 1929), Gelastocoris flavus flavus (Guérin-Méneville, 1844), Rheumatobates crassifemur crassifemur (Esaki, 1926), Buenoa amnigenus (White, 1879), Buenoa unguis (Truxal, 1953), Martarega brasiliensis (Truxal, 1949), Martarega membranácea (White, 1879), Martarega uruguayensis (Berg, 1883), Rhagovelia tenuipes (Champion, 1898) and Rhagovelia zela (Drake, 1959). We found that the testes of these species can be round, round/spiral, or elongated/spiral. The size of the prophase I cells was found to vary, with the smallest ones being detected in B. micantulum and Rha. zela, the largest in G. f. flavus, and ones of intermediate size in R. c. crassifemur and M. brasiliensis. With respect to the chromosome complement, we verified the presence of 2n = 16 (14A+XY, B. micantulum and G. angulatus), 21 (20A+X0, R. c. crassifemur), 23 (22A+X0, Rha. zela and Rha. tenuipes), 25 (24A+X0, Bu. amnigenus and Bu. unguis; 22A+2m+X0, M. membranacea), 27 (24A+2m+X0, M. brasiliensis and M. uruguayensis), 29 (26A+X1X2Y, B. anurum), and 35 (30A+X1X2X3X4Y, G. f. flavus). We found that the features of spermatogenesis in these species are similar to those of other previously described Heteroptera species, differing only in testicular morphology, chromosome number, and sex chromosome system. 相似文献
10.